Flexible door hinge system

ABSTRACT

1,044,317. Hinges and Pivots. A. &amp; D. FABRICATING CO. Inc. Jan. 13, 1965 [Jan. 16,1964], No. 1451/65. Heading E2F. A door is pivoted about two solid torsion bars 65, 66 each with one end clamped in a rigid quadrangular tube 42 formed integrally with the L-shaped frame 37, 40 supporting the door of plastics material, and the other end clamped in the socket 55 of an adjacent hinge base 53 or 54. The ends of the tube 42 are provided with sleeves 75, 80 encircling and rotatable about the sockets 55. A cam surface 83 on the bottom of the sleeve 80 bears on a pair of rollers 87 and is so shaped that the door rises on opening and thus closes by gravity as well as by the action of the torsion bars, and is held in a closed position. The sockets may be adjusted on the hinge bases to pre-set the hinge to ensure that the door closes.

Sept. 13, 1966 DIRUBBO 3,272,257

FLEXIBLE DOOR HINGE SYSTEM Filed Jan, 16, 1964 INVENTOR.

ANGELO DIRUBBO 56 W [PW ATTORNEYS United States Patent ice 3,272,257 FLEXIBLE DOOR HINGE SYSTEM Angelo Dirubbo, North Chelmsford, Mass., assignor to A 81 D Fabricating (30., Inc., Lowell, Mass., 21 corporation of Massachusetts Filed Jan. 16, 1964, Ser. No. 338,247 10 Claims. (Cl. 160-354) This invention relates to an improved door of the swinging, flexible, transparent type.

It has heretofore been proposed, as in US. Patent 2,279,572 to Kann of Apr. 14, 1942, to provide swinging doors for closing a doorway, each door having a rigid inverted L shaped frame which supports a heavy sheet of transparent plastic material. Such doors are especially useful in factories for permitting lift truck operatives to see traflic coming through from the opposite side of the doorway and to pass through the doorway without scratching, or otherwise damaging, the load or the lift truck.

However, the coil spring hinge suspension system, or inclined cam and roller hinge systems, of conventional doors of this type have certain disadvantages, for example, a prevailing draft or wind will tend to keep the doors slightly ajar at all times, the breakage of a spring causes considerable down time due to its inaccessability and the coil springs, or cam hinges, often present undue resistance to easy passage through the doorway.

The principal object of this invention is to provide swinging doors of flexible material which are resiliently mounted by means of torsion bars, or rods, of solid rubber-like material, such as a neoprene, the bars being slidable in a tube for quick replacement in case of breakage.

Another object of the invention is to provide flexible swinging doors with a rubber-like, torsion rod hinge system while also providing mechanism for preventing undue twist in a short span thereof and for preventing distortion of the rod by the weight of the doors.

A further object of the invention is to provide a pair of flexible swinging doors with elastomeric torsion bars each bar being seated in a socket of square cross section, the socket being encircled by a sleeve of circular cross section to serve as a non yieldable bearing and the sleeve having a groove for seating a corner of the socket to serve as a stop.

Other objects and advantages of the invention will be apparent from the claims, the description of the drawing and from the drawing in which:

FIG. 1 is a front elevation of a pair of swinging doors of flexible material constructed in accordance with the invention;

FIG. 2 is an enlarged, fragmentary front elevation of the device;

FIG. 3 is a bottom view of the upper hinge base with its angularly adjustable socket;

FIG. 4 is a side elevation in half section, and

FIG. 5 is a plan view of the sleeve bearing and stop, in section on line 55 of FIG. 4;

FIG. 6 is a plan view showing the preferred construction of the rigid frame and tube, and

FIG. 7 is a side elevation in half section of the lower hinge base and socket with its cam and cam follower door support.

As shown in FIG. 1, a typical doorway 30 in a manufacturing plant includes the side jambs 31 and 32 which extend from one extremity 33, at floor level, to the other extremity 34, at the lintel, or other upper piece, of the door casing.

A pair of doors 35 and 36 are provided, each door being of heavy, flexible plastic material which is preferably transparent. Each door is supported in an inverted 3,272,257 Patented Sept. 13, 1966 L shaped frame 37 or 38, each frame having a side portion 39 and an upper portion 40 of suitable, substantially rigid, material such as metal sheeting.

conventionally the frames 37 and 38 are hinge pivoted by means of pivot pins, the doors being automatically returned to closed position by inclined cam and roller follower type hinges or by coil spring type hinges.

In this invention, each door and frame includes a hol low, vertical tube 42 or 43, of quadrangular cross section, which preferably is square. As shown in FIG. 6 each tube such as 42 is preferably formed integrally with the side portion 39 of the frame with one half of the tube bent from one sheet metal plate 44 and the other half of the tube bent from the sheet metal plate 45. The plates 44 and 45 are then riveted together as at 46 and 47 to clamp the sheet material of the door therebetween.

Each tube 42, or 43, is of predetermined height, slightly less than the height of the doorway 30, so that the open upper end 48 and the open lower end 49 terminate at a spaced distance from the upper and lower edges of the door frame or door. Each tube also includes a plurality of spaced holes such as 51 and 52 for a purpose to be described.

A pair of hinge bases 53 and 54 are provided for each door, each hinge base having a socket 55 of rectangular cross section and each being adapted to be aflixed at the upper, or lower, extremities 33 or 34 of the door jamb. As best shown in FIGURE 2, each hinge base such as 53 preferably includes the socket 55 and plate 56, the plate 56 being pivotally mounted at 57 to the second plate 58. Means for affixing plate 58 to the floor, or to the lintel of the doorway are provided by the screw holes 59. Plate 56 includes an arcuate slot 61 for a set screw 62 threaded in plate 58 so that the socket may be secured at various angles on the fixed plate 58, to compensate for any prevailing wind or draft. The sockets 55, of the hinge bases 53 and 54 are coaxially aligned with the vertical axis of the tube 42 and one exterior angular corner 63 of the upper hinge base is on the centre line of plate 56 to serve as a stop in a manner to be explained.

As best shown in FIGURE 2, a pair of torsion bars, or rods 65 and 66 are provided for each door, the torsion bars being of solid, flexible, resilient, yieldable material for example, rubber-like, elastomeric or the equivalent. The preferred material for the purpose is neoprene or compositions containing a substantial proportion thereof. Each torsion bar such as 65 is quadrangular in cross section, preferably square, to slidably fit within the tubes 42 or 43 and within the sockets 55. Each torsion bar such as 65 or 66 has one end 67 seated in a socket 55 of one of the hinge bases 53 or 54 and the other end 68 seated within the adjacent open end 48 or 49 of a tube 42 or 43. To avoid undue twisting, resulting in shearing, the predetermined length of the tubes and the height of the socket are so arranged as to expose at least two or three inches of the torsion bar, as at 69 and 70, the exposed portion being free to twist without confinement.

Each torsion bar such as 65 or 66 has its inner terminal end 71 in engagement with a pin 73 passing through one set of holes 51 or 52 or 72 to maintain the bar in position within the tube. In case of fracture of the bar due to fatigue, it is only necessary to withdraw the pin, slide a new portion of the bar from the tube into the socket and reinsert the pin in the next set of holes.

As shown in FIGURE 4, a sleeve 75 of circular cross section is affixed to the upper open end 48 of each tube to extend upwardly and encircle the adjacent socket 55 of the hinge base 53. The sleeve 75 has an inside face 76 which loosely fits around the angular corners of the socket to serve as a pivot bearing of rigid material. It, therefore, prevents the upper end of the bar from pulling out of the socket due to the weight of the door, or from becoming slightly deformed and bowed. A vertcial groove 77 in the inside face 76 registers with the exterior angular corner 63 of the socket so that the door automatically stops in closed position.

As shown in FIGURE 7, a similar sleeve 80 of circular cross section is aifixed to the lower open end 49 of each tube to encircle the adjacent socket 55 of the hinge base 54. Sleeve 80 also includes a vertical groove 81 in the inside face 82, similar to groove 77 and for the same purpose.

Each lower hinge base 54 also preferably includes a slightly sloping cam surface 83 on the lower rim thereof, having a pair of opposed arcuate recesses 84 and 85 therein, each for one of a pair of opposed roller cam followers 86 and 87. Each cam follower rotates on a fixed axis in the upstanding supports 88 and 89 which are tu-rna-ble with the plate 56 of the base 54. The recesses 84 and 85 act as stops to bring the door to closed position and hold it in that position against normal drafts. However when the door is pushed for opening, there is no deformation of the torsion bar, but instead the cam action is balanced on each side of the door, the door lifts slightly and the in clined cam face 83 rides on the rollers. The torsion rod returns the door to its closed position, but if the reaction of the rod is slow near the end of its return twist, the gravitational effect of the cam assures a rapid final closing action. The cam and rollers also support the door against any tendency for the weight of the door to compress the torsion rod.

I claim:

1. In a swinging door of the type formed by a sheet of heavy, flexible, transparent material having its upper edge, and one side edge, supported in an inverted, L shaped rigid frame the combination of;

a hollow vertical tube of quadrangular cross section, integrally fixed to the side portion of said L shaped frame, said tube being of predetermined height and having opposite, open ends;

a pair of hinge bases, each having a socket of quadrangular cross section, and adapted to be afiixed at the upper, and lower, extremity of a door jamb in coaxial alignment with the other, and

a pair of solid torsion bars of flexible resilient material, each bar having one end seated in one of said sockets and the other end seated in the adjacent open end of said tube.

2. A combination as specified in claim 1, wherein said hollow vertical tube and said side portion of said frame are formed of two sheets of metal with said material clamped therebetween, each said sheet being bent at its free vertical edge to define one half of said tube.

3. A combination as specified in claim 1 wherein each said hinge base includes an integral plate pivotally mounted on a second plate, a set screw and arcuate slot connection between said plates and means for affixing said second plate to a door casing, whereby said hinge base may be adjusted to compensate for a prevailing draft through a doorway.

4. A combination as specified in claim 1 plus a pair of sleeves of circular cross section and rigid material, each fixed to said tube and extending beyond the adjacent open end thereof to encircle the socket of the adjacent hinge base, a cam surface on the rim of the lower sleeve and a pair of oppositely disposed roller cam followers fixed to the adjacent hinge base and engaging said cam surface, said cam surface having oppositely disposed arcuate recesses for receiving said followers and serving as a stop for said door.

5. A combination as specified in claim 1 wherein the predetermined height of said tube is substantially less than the distance between said sockets and at least two inches of each said bar is exposed between each socket and the adjacent open end of said tube to permit free twisting of said bar without fracture.

6. A combination as specified in claim 1 wherein each said tube is provided with a plurality of spaced holes, a pin is detachably secured in said tube and the inner end of each bar engages one of said pins in a registering set of holes, whereby said torsion bar may be axially adjusted to compensate for any breakage thereof.

7. A combination as specified in claim 1 plus a sleeve of circular cross section fixed to said tube and extending above said open upper end thereof to encircle the socket of the adjacent hinge base, said sleeve being of rigid material and forming an unyieldable pivot bearing for said door.

8. A combination as specified in claim 7 wherein said sleeve includes a vertical groove in the inner face thereof adapted to receive an angular exterior corner of said socket for serving as a stop for said door.

9. A pair of swinging doors of heavy, flexible, plastic material for closing a doorway, said doors each having a hollow metal tube of square cross section extending along its vertical outer edge and defining the vertical pivot axis thereof;

a pair of hinge bases, each having a socket of square cross section and each mounted in said doorway at an opposite end of said pivot axis;

a pair of torsion bars of synthetic rubber-like material, each having one end seated in one of said sockets and the other end seated in the adjacent end of said tube, and

a sleeve of circular cross section fixed to each end of said tube and encircling the socket of the adjacent hinge base for turning thereon.

10. A combination as specified in claim 9 wherein said tube is of substantially less height than the distance between said sockets and at least two inches of each said torsion bar is exposed between said tube and the adjacent socket for enabling free twisting of said bars without fracture.

References Cited by the Examiner UNITED STATES PATENTS 2,279,572 4/1942 Kann 89 2,783,833 3/1957 Cann 160354 2,827,117 3/1958 Bateman 160-354 HARRISON R. MOSELEY, Primary Examiner.

P. C. KANNAN, Assistant Examiner. 

1. IN A SWINGING DOOR OF THE TYPE FORMED BY A SHEET OF HEAVY, FLEXIBLE, TRANSPARENT MATERIAL HAVING ITS UPPER EDGE, AND ONE SIDE EDGE, SUPPORTED IN AN INVERTED, L SHAPED RIGID FRAME THE COMBINATION OF; A HOLLOW VERTICAL TUBE OF QUADRANGULAR CROSS SECTION, INTEGRALLY FIXED TO THE SIDE PORTION OF SAID L SHAPED FRAME, SAID TUBE BEING OF PREDETERMINED HEIGHT AND HAVING OPPOSITE, OPEN ENDS; A PAIR OF HINGE BASES, EACH HAVING A SOCKET OF QUADRANGULAR CROSS SECTION, AND ADAPTED TO BE AFFIXED AT 